One difficulty that may be faced by designers and manufacturers of projection systems is that of providing adequate cooling. For example, lamps in these systems may produce a great deal of light. In LCD based projectors, much of that light may be absorbed in the projection system by polarizers and by LCD panels, along with various other components. When these components block or absorb light, heat may be produced. Excessive heat may lead to component failures.
Prior efforts to cool various components in projectors, such as LCD based projectors, include the use of blowers or fans to force air through certain areas of the projector, including in an LCD based projector the area around an x-cube. An x-cube is a prism device that receives multiple beams of light, combines the multiple beams of light, and outputs a composite beam of light. An x-cube is typically surrounded by several inlet polarizers, LCD panels, and exit polarizers. Additional fans or blowers may be used to cool other parts of the projector.
FIG. 1 is a perspective view of a portion of a prior projector 100. The shown portion may be referred to as a projector engine. The term “projector engine” as used herein is meant to denote a portion of a projector that includes various optical components. The term “projector engine” is meant to include a wide range of possible types and arrangements of optical components. Projector engine 100 includes a beam of light 105 produced by a lamp (not shown). Beam of light 105 makes its way through projector engine 100, with beam 105 possibly being split into red, green, and blue beams of visible light. These beams eventually arrive at an x-cube 140 (the x-cube is located beneath the cover labeled 140). X-cube 140 combines the beams and produces an output beam 115 that is propagated through a projection lens 110. As the red, green, and blue beams approach x-cube 140, the individual beams may pass through LCD panels and inlet and exit polarizers (not shown). The polarizers and LCD panels may then heat up and, in some cases, overheat. Here, blowers 120 and 130 are utilized to force air into the area of projector engine 100 surrounding x-cube 140. This may produce cooling of the optics.